In this chapter, we present the predictive multi-theory multiscale framework called consistent embedding. The characteristics of a consistently embedded set of theories is defined and illustrated by four examples. These examples show the coupling between quantum mechanical and atomistic scales, short and long time microstructural evolution, and chemical reactivity and flow dynamics. A final example carries a cautionary message in that all embedding are not necessarily consistent. Overlapping tests are essential to the establishment of a predictive multi-theory multiscale simulation.